Apparatus for polishing the pivots of escapements and other clock-wheels.



C. ROSAT. APPARATUS FDR PGUSHING THE PWOTS 0F ESCAPEMENTS AND OTHER CLOCK WHEELS.

' APPLICATION mm NOV. 19, 1 913 1,235,503, Patented July 31,1917.

3: mania X if 7m7-"Zasjfosmti' TTfi @TATlE PATENT CHARLES ROSAT, OF BOUDIRY, SWITZERLAND.

APPARATUS FOR POLISHING THE PIVOTS OF ESCAPEMENTS AND OTHER CLOCK- WHEELS.

Specification of Letters Patent.

Patented July 31, 1917.

Application filed November 19, 1913. Serial No. 801,785.

To all whom it may concern:

Be it known that 1, CHARLES ltosa'r, a citizen of the Swiss Republic, and resident of Boudry, Canton of Neuchfi-tel, Switzerland, have invented a new and useful Apparatus for Polishing the Pivots of Escapements and other Clock-*Nheels, of which the following is a full, clear, and exact specification.

Theobject of the present invention is to provide ways and means for polishing the pivots of escapements and other clock wheels easily, quickly and perfectly, also to render it capable of being eiiected by any one not very expert. The apparatus which forms the subject matter of the invention is so arranged that without worrying about the final diameter of the pivot and the further operations the polishing steel has simply to be worked backward and forward while all other precautions are taken care of by the apparatus itself. This apparatus is characterized by the feature that the pivot to be polished, fixed on one side in a rotating holder of known kind, is carried with its thicker body portion in an indented bearing adjustable according to the thickness of the pivot so as to have its indentation in one line with the axis of the latter, while the polishing steel has its back surface supported upon an abutment arranged to give the working pressure by spring or welght means and is held by this against the work piece (pivot) until it contacts with an adjustable stop adjusted in accordance with the final diameter of the pivot in such a way that with the pivot quite free, it allows of uniform and complete circular polishing of the pivot to the desireddiameter merely by working the polishing steel backward and forward. When the pivot bearing and the polishing steel stop are once adjusted, no attention need be paid to the remaining stages of the work; the working pressure is automatically exerted and need no longer be left to the mere feeling of the operator; the pivot is uniformly polished along its whole length; the central guiding of the pivot during its rotation is insured by the indented bearing and keeping to the desired diameter is insured by the stop for the polishing steel preferably consisting of a micrometer screw.

The drawing illustrates one example of construction of the subject matter of the invention,

Figure l is a front view,

Fig. 2 a side view, and

Fig. 3 a plan of the apparatus.

Fig. at illustrates an escapement and shows particularly the shape of the pivot of the same.

3 A holder or chuck c of known construction is rotatably mounted in the cheeks a of the frame F) of the apparatus. This chuck c which is driven by any means through a grooved pulley, consists, for example, of three clamping jaws which may be opened by pressing on a knob (Z and may be closed by the action of a spring on releasing said knob. The escapement or the clock wheel is fixed in the chuck c by one pivot while the other freely projecting rough pivot to be micrometer screw 2' which is screwed into the arm and upon pressing on the thumb piece 7' of the arm 9 insures the central and steady rotation of the escapement under the drive of the chuck 0.

A vertical abutment bolt is is mounted in the frame I), the upper end of which is beveled off and which is by means of. a helical spring Z (Fig. 2) pressed, steadily upward. The uppermost position of this bolt 70 is limited by an underneath stop head on. The bolt it serves as an abutment for a polishing steel n shown in Figs. 1 and 2, acting either through an abrasive or provided with a In order to polish the freely projecting rough pivot as well as the conical joining part it is sufficient to draw the polishing steel n to and fro in its longitudinal direction upon the upper edge of the supporting bolt during the rotation of the chuck 0 until 'when the steel is contacts with the screw stop 0 the polishing is completed to the de sired diameter.

By raising the arm g and the parts carried by it the escapeinent or the like may conveniently be fixed in position and ex amined.

What I claim is:

1. An apparatus for polishing the pivots of escapement and other clock wheels, comprising in combination a rotatable holder for holding the work piece with the pivot to be polished in a freely projecting condition, an adjustable. indented bearing for receiving in its indentation the thicker body portion of the pivot, a, movable polishing steel, a vertically movable abutment for supporting the polishing steel to be moved to and fro on said abutment, pressure means yieldingly acting upon said abutment to raise it and to thus press the polishing steel with its working face from below against the pivot to be polished and an adjustable stop adjusted according to the final diameter of the pivot and designed to limit the upward movement of the polishing steel under the action of said pressure means, substantially as and for the purpose described.

An apparatus for polishing the pivots of escapement and other clock wheels, comprising in combination a rotatable holder for holding the work piece with the pivot to be polished in a freely projecting condi tion, an adjustable indented bearing for receiving in its indentation the thicker body portion of the pivot, a movable polishing steel, a vertically movable abutment bolt for supporting the polishing steel to be moved to and fro on said abutment bolt, spring means acting upon said abutment bolt to raise it and to thus press the polishing steel with its working face from below against the pivot to be polished and an adjustable stop adjusted according to the final diamceiving in its indentation the thickerbody portion of the pivot, a movable polishing steel, a vertically movableabutment bolt beveled oil at its upper end and arranged to support the polishing steel to be moved to and fro on said abutment, bolt, spring means acting upon said abutment bolt to raise it and to thus press the polishing steel with its working face from below against the pivot to polished and an adjustable stop adjusted 7 according to the final diameter of the pivot and designed to limit the upward movement of the polishing steel under the action of said spring means, substantially as and for thepurpose described.

at. An apparatus of the character described having in combination a rotatable work holder, a support for polishing means inovable transversely to the rotative axis of the work holder and engageable with the work held thereby to polish the same, and an adjustable stop for limiting the movement of said polishing means toward the work.

5. An apparatus of the character described having in combination a rotatable work holder, a support for polishing means movable transversely to the rotative axis of the work holder and engageable with the work held thereby to polish the same, a stop for limiting the movement of said polishing means toward the work, and a micrometer screw for adjusting said stop;

In witness whereof I have hereunto signed my name this 27th day of October 1918, in the presence of two subscribing witnesses.

CHARLES ROSA'I. llitnesses FLITZ COSANDIER, Annnn Favs.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

